When AirAsia X launched its "no-frills" service between Kuala Lumpur and London Stansted earlier this month, one of the points raised was that the vast majority of seats on its two A340-300 aircraft would be economy, and that the seat pitch would be just 32in.

Yet a glance at the seat pitches of major airlines suggests that AirAsia X is doing little out of the ordinary. In fact, it is marginally more generous than some of the flagship carriers, such as British Airways.

The good news for passengers is that seat pitch has already been squeezed as far as airlines feel they can get away with. The bad news is that the credit crisis has ensured that few airlines will feel able to increase leg space. "Seat pitch equals revenue, and that equals how much the airlines will lose or, if they're lucky, make this year," said Peter Miller, marketing director of Skytrax, adviser on quality to airlines and airports. "If you have a seat pitch of 31in rather than 34in, then you carry an extra 25 to 30 passengers. All the major airlines will get away with as little as they can."

Instead, some airlines are looking to increase capacity by installing more seats along rows. Emirates has introduced 10 seats across the aisles of its 777s, while Air France also recently installed 10-seat rows on some aircraft – equating to an extra 35 passengers or so per flight.

The seat pitch is the distance between the rows of seats and is measured from the back of one seat to the back of the seat behind. UK regulations set by the Civil Aviation Authority say that, in practice, the minimum seat pitch must be 28in. The UK is thought to be the only country with a minimum seat pitch. Yet seat pitch per se does not reflect the amount of legroom available, as this also depends on the size and thickness of seat.

"Seat pitch is an element in airline costings, but it isn't fundamental," said Neal Weston of the British Air Transport Association. "There are other issues, such as ancillary charges, luggage, and how web-based customers are."

A spokeswoman for BA echoed this view. "We select our seat pitch based on a number of factors," she said. "We need to ensure the seats are comfortable for customers, and make the most use of the cabin floor space we have."

Generally, apart from securing an emergency row seat, bulkhead seat or just an aisle seat, there appears little that passengers can do to ease cramped conditions. Even the A380 offers a seat pitch of 32in. The effect on such a wide-bodied aircraft is to create space for 399 economy passengers, but the result is what some people have described as a claustrophobic feeling on the lower deck, which has three long segments, each curtained off, of economy seats in 3-4-3 format.

Possible solutions include staggering seats to free up arm and shoulder space; and overlapping arm rests to increase seat width. Cathay Pacific brought in a fixed-back seat that can recline without impinging on the space behind or in front of you. Singapore Airlines offers a 32in pitch, but has also designed an economy seat that creates more room.

If you are lucky, one of the few airlines with a good-sized seat pitch will be flying to your destination, and Skytrax pin points Asiana Airlines as having the amplest, at 34in. "Such airlines know they could squeeze more people on but they use this as a key selling point," said Mr Miller. Similarly Thai Airways and Malaysia Airlines, which generally fly older aircraft, offer more generous seat pitch.